changed denominator for covariance matrix
changed denominator for covariance matrix

pearsonlab/thunder,poolio/thunder,broxtronix/thunder,j-friedrich/thunder,mikarubi/thunder,zhwa/thunder,thunder-project/thunder,mikarubi/thunder,oliverhuangchao/thunder,kcompher/thunder,oliverhuangchao/thunder,zhwa/thunder,poolio/thunder,kunallillaney/thunder,pearsonlab/thunder,kcompher/thunder,broxtronix/thunder,j-friedrich/thunder,jwittenbach/thunder,kunallillaney/thunder